I don't think the show is a ripoff of either Time Trax or Time Cop. Time Cop was more about preventing the misuse of time travel than anything else, while Time Trax, as I remember, was simply (mostly) about rounding up the fugitives. Continuum is more nuanced. If nothing else, the criminals have a goal that they themselves can't really benefit from and, if they had avoided collateral damage, they could almost come across as being the good guys.

The great thing about time travel is that it doesn't matter how many people you murder in the future, when you go back time all of those deaths will be nullified. They haven't been born yet so you couldn't have killed them. Assuming that history can be changed, you effectively get the slate wiped every time you go back.